Rod of dental impression material



April 29, 1952 w. L. WADE 2,594,830

ROD. OF DENTAL IMPRESSION MATERIAL Filed Aug. 8, 1949 F/GJ. [-7 1 3.

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FIG'QQ. V 4/ 6 Patented Apr. 29, 1952 OFFICE 2,594,830 ROD F DENTAL IMPREssI'oN MATERIAL William Leonard Wade, Birkdale, Southport,

England Application August 8, 1949, Serial No.-1 09,082 In Great Britain September 28, 1948 2 Claims. (01. 32-19) This invention relates to an improved method of and means for preparing sets of artificial teeth. In the present usual practice of dentistry, after impression moulds of the upper and lowerparts of the mouth have been taken and plaster casts or models made from the moulds, these are coated with wax sheetin and wax bite blocks pressed thereon to make the bite rim. The bite blocks are at present prepared by rolling up a warmed wax sheet to form a thick wax rod, which is then bent round to the shape of the plaster model-to make the bite rim therefrom. The preparation of bite blocks from wax sheetin in this way take up considerable time and an object of the present invention is to economize the time of the practitioner by providing ready prepared wax bite blocks or rims suitable for taking slight impressions thereon direct from the patients ridges of the jaws. The normal present procedure also necessitates two visits by the patient, a primary visit for taking the impressions for the plaster models and a subsequent visit for taking the bite of the blocks prepared therefrom. A further object of the present invention concerns means whereby the jaw impressions for casting the plastermodels, also slight jaw ridge'impressions taken direct on the wax bite blocks, and the bite position, may be taken on the one occasion, thus ensuring a considerable saving of time to both the dentist and patient.

According to this invention a bite block for use in dentistry consists of a length of wax or impressionable material made in curved or arch formation conforming to the curvature of.the

human jaw and longitudinally channeled or grooved along one face. The invention also in cludes a channeled rod form of wax or impressionable material for making such a curved block. Further features of the invention are described in the following specification and set out in the claims.

In the accompanying explanatory drawings:

Fig. 1 is a plan,

Fig. 2 an end view and Fig. 3 a perspective view of a ready prepared bite block in curved or arched formation.

Fig. 4 shows the present method of taking an impression on a bite block from the plaster cast model of the jaw.

Fig. 5 is a view of a rod form of wax or the like slotted on one side for facilitating bending into the curved form of bite block shown in Fig. 6.

Fig. 6 is a plan of the completed bite block.

Fig. 7 is a perspective view of an alternative 'slotted form of ready prepared bite block in curved or arched formation,

Fig. 8 is a view of a rod of wax.

Fig. 9 is an alternative form of the wax or like red shown in Fig. 8.

In carrying out the invention, and referring in the first place to the form of bite block shown 1' in Figs. 1 to 3 wax blocks l of the desired thickness are provided of curved or arched iormation in plan and conforming approximately to the curvature of the jaw. The surface of the block to be placed on the ridge of the patients jaw when taking an impression and the bite is. channeled or grooved at 2 throughout its length, the groove beingpreferably of curved cross-section as shown. The impressions of the. patients upper and lower jaws are taken'direct on two :such shaped blocks which have been suitably warmed to soften the wax, .any slight modification of the curvature of the blocks to suit the particular configuration of the patients jaws being made by slightly bending the blocks. The two wax blocks or rims thus impressed and after being set by immersion in cold water are then again placed in the patients mouth and shaped by the dentist to obtain the correct bite position, after which they are positioned on the plastercasts .in an articulator for production of the sets of artificial .teeth in known manner. In present practice after plaster cast models 3 of the pa tients jaws having been prepared and served with wax sheeting 4, Fig. 4, bite blocks lc prepared by rolling up wax sheeting are pressed in position on to the sheeting 4, as indicated to ob-' tain impressions from the plaster cast models. f

Alternatively, instead of wax blocks already formed in curved or arch shape, -as.'in".F?igs; -1,.i 2 and 3, the wax may be made in straightirods'v 5, Fig. 5, channeled beneath, as at 2, and of any suitable length and thickness, the rod when required being bent into the desired curved shape, Fig. 6. One side of the rod may be formed with a series of cuts or slots 6, preferably of V-shape, to allow for and facilitate the bending of the length into the desired curve. With either form, the ready prepared arched block or the straight rod, the upper surface, that is the contacting bite surface, may have a series of recesses or grooves formed therein, which may be provided by continuing across the upper bite surface of the block the cuts or V-slots 6 on the side.

By providing arch shaped blocks or thick rods of wax as described with channeled surfaces, considerable time is saved by obviating the present comparatively lengthy operation of rolling up and moulding the wax sheet into shape, the whole operation being also rendered more cleanly.

Instead of separate upper and lower bite.

clocks, a single unit block Hz, Fig. 7, may be provided, of wax or other suitable impressionable material, the block being again of curved or arched form, conforming approximately to the curvature of the jaws, and having one surface, that for positioning on the lower jaw, of channelled formation 2a. In the opposite surface of the block are formed one or more, preferably two, transverse open slots or notches 8, leaving three crests l' or high point or surfaces on that side of the block. The surface of these crests may also be channelled.

After impressions of the patients jaws have been taken for the production of the usual plaster models, a shaped bite block la is prepared by softening the wax in the channel groove 2a of its lower surface, and is then positioned in the patients mouth, the dentist placing his fingers in the two notches 8 and pressing down the bite block firmly on the ridge of the lower jaw, so obtaining an impression thereof. The patient then closes his upper jaw down on the block, the dentist noting the contact of the jaw and, having removed the block from the patients mouth, shaves off or otherwise removes the higher contact points from the crests I of the block until a correct bite closure is obtained. The practitioner then with a hot knife or other implement softens the tops of the three high parts or crests of the block and again setting the bite block in position on the lower jaw and holding it down firmly with his fingers, the patient bites, thus producing an impression of the ridge of the upper jaw on the crests I, so that when the block is finally removed it bears distinct impressions of the upper and lower jaw ridges of the patients mouth and also registers a correct bite position. The plaster cast models are then fitted into these impressions in the upper and lower surfaces of the unit bite block la, and are then set in the articulator in known manner for the subsequent production of the complete sets of artificial teeth. In this way the impressions for the plaster cast models and a record of the correct bite on the bite block may be obtained during a single visit by the patient.

Instead of ready prepared bite blocks to of curved shape, straight rods lb of wax or other impressionable material may be provided longitudinally channelled beneath at 2b and having transverse notches 8a, such rods being bent into the desired curvature as required-and in order to facilitate such bending, one side surface of the rod lb may be vertically slotted as previously described with reference to the rod form shown in Fig. 5.

The notches in the bite block for inserting the fingers to press the block on the lower jaw and also hold it while the bite of the upper jaw is taken, are also of service to the practitioner by enabling him to see the position of the patients tongue during the operation, and though the impression taken in the bite block may be slight it is quite definitely sufficient for the purpose, and could be made very pronounced by using more impressionable material than wax.

While the bite blocks have been referred to as wax blocks, it is to be understood that they may be made of any other material which is adapted for taking an impression of the jaw ridges of the patient, and such blocks, instead of being made entirely of impressionable material, may be composite and have only the channel or groove in the jaw contacting surface and the opposite surface served with such impressionable material, but by making the blocks entirely of wax their shape may be slightly modified when required by warming and bending to adjust them to the curvature of the patients mouth.

The ready prepared curved blocks may be made in several sizes.

What I claim is:

l. A rod of impressionable material for use in forming a curved dental bite block, the rod beingof substantially rectangular section and having one face longitudinally channelled and another face, adjoining said channelled face, formed with a series of transverse slots for facilitating bending of the rod into a curved bite block.

2. A rod of impressionable material for use in forming a curved dental bite block as claimed in claim 1 in which the face of the rod opposite to the longitudinally channelled face is formed with open transverse notches suitable for insertion of the fingers therein.

WILLIAM LEONARD WADE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 90,706 Von Bonnhorst June 1, 1869 457,937 Sabin Aug. 18, 1891 2,027,373 Eden Jan. 14, 1936 OTHER. REFERENCES Detroit Dental Mfg. Co. Catalog, Feb. 10, 1934. page 6, copy in Div. 55. 

